JP2844106B2 - Method for producing linear block copolymer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) The present invention uses a diepoxy compound having a specific structure to improve productivity, and improve color tone / transparency and thermal stability (when heated) The present invention relates to a novel method for producing a block copolymer comprising a monoalkenyl aromatic compound and a conjugated diene, which has an excellent balance between color tone and odor) and mechanical strength.

(Prior Art) In an inert hydrocarbon solvent, an organolithium compound is used as an initiator to polymerize a monoalkenyl aromatic compound, subsequently polymerize a conjugated diene, and again polymerize a monoalkenyl aromatic compound to form a block copolymer. A sequential polymerization method for obtaining a polymer [for example, U.S. Pat.
-23798) is known, but there is a problem that productivity is poor.

In order to improve this problem, a method of polymerizing a monoalkenyl aromatic compound, subsequently polymerizing a conjugated diene, and reacting a bifunctional coupling agent with the obtained living polymer to obtain a linear block copolymer. Has been proposed.

For example, as a bifunctional coupling agent, a dihalogenated silane compound such as dichlorodimethylsilane [for example,
JP-A-61-291610], dihalogenated hydrocarbon compounds such as dibromoethane (for example, JP-A-61-291610)
No., German Patent No. 1,520,864 (Japanese Patent Publication No. 40-249)
No. 15)], acid chlorides such as acetyl chloride [Kokiaki Tokuho
No. 42-24174), but the block copolymer obtained by this method is inferior in transparency, and in the processing step and the final use, it is contained in the block copolymer. There is a problem that it has metal corrosiveness presumed to be caused by the remaining halogen and also impairs thermal stability.

For this reason, various types of bifunctional coupling agents other than halogen compounds have been proposed. For example, monoesters such as phenyl benzoate and ethyl acetate [for example, U.S. Pat.
No. 6,301 (JP-B-49-34478)], but the block copolymer obtained by this method is liable to impair the color tone (colored yellow) and has a by-product of the reaction. (Alcohols, phenols) need to be removed.

Also, lactones such as γ-butyl lactone (for example,
The block copolymer obtained according to U.S. Pat. No. 4,308,364 (JP-A-57-96004) has problems that the color tone is impaired (colored yellow) and the coupling efficiency is insufficient.

In addition, a specific polyfunctional compound having a diglycidylamino group (see Published Patent Publication WO 87/05610) has also been proposed, but since this compound has self-crosslinking properties and is an unstable compound, There is a problem in reproducibility of ring efficiency.
In addition, diisocyanates, diketones, amides, oxygen, and the like have been proposed, but they have problems such as insufficient coupling efficiency and impairing the color tone of the obtained block copolymer.

(Problems to be Solved by the Invention) The present invention has found an epoch-making bifunctional coupling agent which has overcome various problems associated with the use of a conventional bifunctional coupling agent, and The object of the present invention is to provide a method for producing a block copolymer comprising a conjugated diene.

(Means for Solving the Problems) The present inventors have conducted intensive studies in order to develop the above-mentioned preferable production method, and as a result, have found that a diepoxy compound having a specific structure can be adapted to the purpose. The present invention has been completed based on this finding.

That is, the present invention provides a method for producing a block copolymer using a monoalkenyl aromatic compound and a conjugated diene monomer in an inert hydrocarbon solvent using an organolithium compound as an initiator; A block copolymer consisting of a polymer block mainly composed of a monoalkenyl aromatic compound and a polymer block mainly composed of a conjugated diene is polymerized, and the peak molecular weight of the block copolymer is determined by gel permeation chromatography (GPC). Is 1 × 10 ⁴ to 50 × 10 ⁴ in terms of standard polystyrene, and the total amount of all the monoalkenyl aromatic compounds in the block copolymer is 10 to 90% by weight. And (ii) adding a diepoxy compound comprising at least one compound selected from the following group to the living polymer And providing a coupling reaction by adding 0.1 to 1.9 equivalent ratio with respect to the amount of chromium.

(I) a general formula of the group; Wherein R is Wherein R ¹ and R ² are hydrogen or a C _{1 to} C ₂₀ alkyl group or alkoxy group or a phenyl group or a substituted phenyl group, and R ³ and R ⁴ are a C _{1 to} C ₂₀ alkyl group or an alkoxy group. R ⁵ is a linear or branched C ₁ -C ³⁰ (oxygen atom-containing) hydrocarbon group, l and m are integers from 0 to 4 and n is an integer from 0 to 10 It is. And a hydrogenated diepoxy compound thereof.

(Group II) An alkylene oxide-containing diepoxy compound.

 However, the following compounds are excluded.

Wherein R is R ³ is an alkylene group having 2 to 20 carbon atoms, n
Is an integer of 0 to 10, and the content of the compound having n of ₀ (hereinafter, referred to as n0 isomer) is 95% by weight or more].

(Group III) alicyclic diepoxy compound.

 However, the following compounds are excluded.

Wherein R is Wherein R ¹ and R ² are hydrogen or an alkyl group having 1 to 20 carbon atoms or a phenyl group, n is an integer of 0 to 10,
Compound numbers are 0 (hereinafter referred to as n ₀ body) diepoxy compound content is indicated by the a] 95 wt% or more.

(Group IV) Carboxylic compound-containing diepoxy compounds.

 However, the following compounds are excluded.

Wherein R is Wherein R ¹ and R ² are hydrogen or an alkyl group having 1 to 20 carbon atoms or a phenyl group, n is an integer of 0 to 10,
Compound numbers are 0 (hereinafter referred to as n ₀ body) diepoxy compound content is indicated by the a] 95 wt% or more.

 Hereinafter, the present invention will be described in detail.

Examples of the monoalkenyl aromatic compound used in the present invention include monomers such as styrene, P-methylstyrene, tertiary butylstyrene, α-methylstyrene, and 1,1-diphenylethylene. Is preferred. These monomers may be used alone or in combination of two or more.

Further, as the conjugated diene used in the present invention, for example, 1,3-butadiene, isoprene, 2,3-dimethyl-1,3
-Butadiene, piperylene, 3-butyl-1,3-octadiene, phenyl-1,3-butadiene and the like, among which 1,3-butadiene and isoprene are preferred. These monomers may be used alone or in combination of two or more.

As an embodiment of the living polymer of the present invention, for example,
Formula _{(A-B) p -Li,} (B-A-B) p -Li, (A-B-A) p -Li, ( wherein, A is a polymer mainly composed of monoalkenyl aromatic compound B is a polymer block mainly composed of a conjugated diene, and p is an integer of 1 to 5) alone or in combination.

The polymer block mainly composed of a monoalkenyl aromatic compound is a homopolymer block of a monoalkenyl aromatic compound or a monoalkenyl aromatic compound-conjugated diene copolymer containing more than 50% by weight of a monoalkenyl aromatic compound. The term “polymer block mainly composed of a conjugated diene” means a conjugated diene homopolymer block or a conjugated diene-monoalkenyl aromatic compound copolymer block containing more than 50% by weight of a conjugated diene. When each block is a copolymer, the arrangement of the monoalkenyl aromatic compound and the conjugated diene may be uniform or non-uniform (taper type or the like).

In addition to the coupling reaction of the living polymer represented by the above general formula, living polymers having different composition ratios (structures) may be separately prepared and subjected to the coupling reaction depending on the purpose, or may be reacted with a monomer during polymerization. Living polymers having different compositions (structures) may be prepared by additionally polymerizing an organolithium compound or the like, and subjected to a coupling reaction.

Further, the living polymer represented by the above general formula may be subjected to a coupling reaction with a (co) polymer living polymer mainly composed of an alkenyl aromatic compound or a (co) polymer living polymer mainly composed of a conjugated diene.

In the present invention, the peak molecular weight of the block copolymer immediately before coupling by GPC is 1 × 10 ⁴ to 50 × 10 ⁴ , preferably 3 × 10 ⁴ to 30 × 1 in terms of standard polystyrene.
0 is ⁴ . When the peak molecular weight is less than 1 × 10 ⁴ , the mechanical strength of the obtained linear block copolymer is remarkably reduced, and when it exceeds 50 × 10 ⁴ , the processability of the obtained linear block copolymer is remarkable. Produces a tendency to decrease.

In the present invention, the total amount of all the monoalkenyl aromatic compounds in the block copolymer immediately before the coupling and the linear block copolymer after the coupling reaction is selected in the range of 10 to 90% by weight, and 10 to 60% by weight. When selected in the range of weight%, a linear block copolymer as a thermoplastic elastic body is used,
On the other hand, when it is selected in the range of more than 60% by weight and 90% by weight, a linear block copolymer as a thermoplastic resin is provided. If the total content is less than 10%, the mechanical strength (tensile properties) of the obtained linear block copolymer as a thermoplastic elastic body is significantly impaired. There is a tendency that the mechanical strength (impact resistance) of the linear block copolymer is significantly impaired.

As the inert hydrocarbon solvent used in the present invention, for example, cyclohexane, n-hexane, benzene, toluene, octane and the like and compounds thereof are used, and among them, cyclohexane is preferable. In addition, these inert hydrocarbon solvents include a small amount of polar compounds such as ethers and tertiary amines such as ethylene glycol dimethyl ether, tetrahydrofuran, α- Methoxytetrahydrofuran, N, N, N ', N'-tetramethylethylenediamine and the like, preferably tetrahydrofuran and
N, N, N ', N'-tetramethylethylenediamine may coexist.

The amount used is such that the 1,4 bond amount is 50% or more, preferably 65%.
%, More preferably 80% or more.

Further, when the A and / or B block is a copolymer, a small amount of an alkali metal tertiary alkoxide may coexist in the inert hydrocarbon solvent for the purpose of adjusting uniformity. Examples of the alkali metal tertiary alkoxide include potassium-t-butoxide, sodium-t
-Amyl oxide, cesium-t-butoxide, potassium isopentyl oxide and the like, among which potassium-t-butoxide is preferable.

The organic lithium compound used in the present invention may be a known compound such as ethyllithium, propyllithium, n-
Examples thereof include butyllithium, sec-butyllithium, t-butyllithium, phenyllithium, propenyllithium, and hexyllithium, and particularly preferably n-butyllithium and sec-butyllithium. This organolithium catalyst is used not only as one kind but also as a mixture of two or more kinds.

The amount used is that of the block copolymer just before coupling.
GPC peak molecular weight is 1 × 1 in terms of standard polystyrene
It is selected in the range of 0 ⁴ to 50 × 10 ⁴ .

The temperature in these polymerization reactions is not particularly limited, but is usually selected in the range of 20 to 140 ° C. in consideration of productivity, preferably the polymerization initiation temperature is in the range of 30 to 90 ° C., and the maximum attained temperature is It is desirable to be in the range of 80 to 140 ° C.

Thus, following the step of (i) preparing a living polymer using an organolithium compound as an initiator in an inert hydrocarbon solvent, (ii) adding a specific diepoxy compound batchwise or continuously, The living polymer is subjected to a coupling reaction in a temperature range of ° C.

That is, the diepoxy compound used in the present invention must contain at least one compound selected from the following group.

(I) a general formula of the group; Wherein R is Wherein R ¹ and R ² are hydrogen or a C _{1 to} C ₂₀ alkyl group or alkoxy group or a phenyl group or a substituted phenyl group, and R ³ and R ⁴ are a C _{1 to} C ₂₀ alkyl group or an alkoxy group. R ⁵ is a linear or branched C ₁ -C ³⁰ (oxygen atom-containing) hydrocarbon group, l and m are integers from 0 to 4 and n is an integer from 0 to 10 It is. And a hydrogenated diepoxy compound thereof.

(Group II) An alkylene oxide-containing diepoxy compound.

(Group III) Alicyclic diepoxy compounds.

(Group IV) A diepoxy compound containing a carbocyclic compound.

(I) Specific examples of the group include: And the like, but are not limited thereto.

The n number of the diepoxy compound used in the present invention is 0 to
It is an integer in the range of 10, preferably 0 to 15, more preferably an integer of 0 to 3. For compounds where n exceeds 10,
Not only is it not possible to obtain sufficient coupling efficiency, but also the viscosity is remarkably increased (in extreme cases, it is solidified), and it tends to be difficult to handle.

In addition, the content of the compound having n = ₀ (hereinafter abbreviated as n0 isomer) is preferably 85% or more, more preferably 95%, in terms of coupling efficiency.
% Is preferable.

(II) Specific examples of the group include: And the like, but are not limited thereto.

(III) Specific examples of the group include: And the like, but are not limited thereto.

(IV) Specific examples of the group include: And the like, but are not limited thereto. In the group (IV), the compound a type and the compound b type are preferable in terms of handling.

Furthermore, among the above-mentioned groups, many of the groups (III) and (IV) have problems in terms of safety and hygiene such as skin irritation, and thus require careful handling. Therefore, the groups (I) and (II) are preferred.

In the diepoxy compound (except group III) used in the present invention, the total chlorine (by-product or residual) derived from epichlorohydrin, which is one of the starting materials, is 1
% By weight or less, particularly preferably 0.5% by weight or less. When the total chlorine content exceeds 1% by weight, the block copolymer obtained by the coupling reaction clearly shows a branched shape in addition to a linear shape, and furthermore, the thermal stability of the obtained block copolymer is reduced. A tendency to impair.

The diepoxy compound used in the present invention may be a single group of each group, a mixture of the same group or different groups, or a diepoxy compound other than the present invention [for example, bisphenol A (F, AD) type diglycidyl ether].

The diepoxy compound of the present invention may be in the form of a stock solution or a solution (for example, diluted with the above-mentioned inert hydrocarbon solvent or the like),
Further, it is used in a heated state as required.

The amount used is in the range of an equivalent ratio of 0.1 to 1.9 based on lithium of the living polymer. In particular, when the corresponding ratio is selected in the range of 0.5 to 1.5, and more preferably 0.8 to 1.2, a linear block copolymer having excellent mechanical strength is obtained.

The coupling reaction is carried out almost instantaneously, but it is usually preferable to carry out the reaction for 1 to 30 minutes.

After completion of the coupling reaction, if necessary, water, alcohol, acid or the like is added to deactivate the active species, and the polymer is subjected to a known polymer separation method, for example, steam stripping, a drying step, and then the wire according to the present invention. A block copolymer is obtained.

If desired, after completion of the coupling reaction (if necessary, after deactivating the active species with water or the like), hydrogenation is carried out partially or completely by a known hydrogenation technique, and hydrogenation is carried out by the polymer separation method described above. The modified linear block copolymer can be obtained or further modified with various modifiers (for example, maleic anhydride) by a known technique to obtain a modified linear block copolymer.

In addition, an antioxidant, a light stabilizer, an antiblocking agent, a softener, and the like can be added to the linear block copolymer obtained by the present invention.

As the antioxidant, for example, 2,6-di-t-butyl-4-methylphenol, n-octadecyl-3-
(4'-hydroxy-3 ', 5'-di-t-butylphenyl) propionate, 2,2'-methylenebis (4-methyl-6-t-butylphenol), 2,2'-methylenebis (4-ethyl- 6-t-butylphenol), 2,4-
Bis [(octylthio) methyl] -o-cresol, 2
-Tert-butyl-6- (3-tert-butyl-2-hydroxy-5-methylbenzyl) -4-methylphenyl acrylate, 2,4-di-tert-amyl-6- [1- (3,5- Di-t
-Amyl-2-hydroxyphenyl) ethyl] phenyl acrylate and the like; dilauryl thiodipropionate, lauryl stearyl thiodipropionate, pentaerythritol-tetrakis (β-lauryl thiopropionate) and the like Tris (nonylphenyl) phosphite, tris (2,
Examples thereof include phosphorus-based antioxidants such as 4-di-t-butylphenyl) phosphite.

Examples of the light stabilizer include 2- (2'-hydroxy-5'-methylphenyl) benzotriazole,
-(2'-hydroxy-3 ', 5'-tert-butylphenyl) benzotriazole, 2- (2'-hydroxy-
Benzotriazole UV absorbers such as 3 ', 5'-di-t-butylphenyl) -5-chlorobenzotriazole, benzophenone UV absorbers such as 2-hydroxy-4-methoxybenzophenone, or hindered amine light stabilizers And the like.

Examples of the antiblocking agent include higher fatty acids,
Examples include metal salts of higher fatty acids, waxes, fatty acid amides, fatty acid esters, inorganic metal salts and hydroxides.

Examples of the softener include naphthenic, paraffinic and aroma-based process oils and mixed oils thereof. Of these, naphthenic, paraffinic and mixed oils are preferable.

EXAMPLES Hereinafter, the present invention will be described with reference to examples, but these examples do not limit the present invention.

 In addition, various measurements followed the following method.

Measurement of Physical Properties of diepoxy compounds; n number and n ₀ body content; GPC [apparatus is Waters, column, in Showa Denko of Shodex K801, K802, K803 of total of three combinations,
R1 and UV (254 nm) were used for the detector. Using chloroform as a solvent, measurement conditions, temperature 35 ° C., a flow rate of 1.0 ml / min, sample concentration 0.1% by weight, from the chromatogram of the a] injection volume 40 [mu, were analyzed n number and n ₀ body content .

 Viscosity: Measured at 25 ° C with a B-type viscometer.

Measurement of physical properties of linear block copolymer; total styrene content; calculated from absorption intensity at 262 nm using an ultraviolet spectrophotometer (Hitachi UV-200).

Peak molecular weight and coupling efficiency: GPC [The apparatus is manufactured by Waters, and the column is a combination of two ZORBAX PSM 1000-S manufactured by DuPont and PSM 60-S in total. Tetrahydrofuran was used as the solvent, and the measurement conditions were as follows: temperature 35 ° C, flow rate 0.7ml / min, sample concentration
0.1% by weight and injection volume of 50 μm) were used to determine the peak molecular weight and the coupling efficiency.

The peak molecular weight is a value converted from the following standard polystyrene (manufactured by Waters) calibration curve.

1.75 × 10 ⁶ , 4.1 × 10 ⁵ , 1.12 × 10 ⁵ , 3.5 × 10 ⁴ , 8.5 × 10 ³ Tensile properties, hardness: Tensile properties are obtained by compressing a 2mm thick sheet at 110 ° C using JI.
The hardness was determined in accordance with SK-6301, and the hardness was determined in accordance with ASTM D-2240.

Thermal stability: 5 g of a sample was placed in a gear oven at 190 ° C., and the odor and color tone after 2 hours were examined. The odor was ranked by a sensory test as ○, Δ, and X (○ was the least irritating odor and was excellent).

Izod impact value: A sample (V notch processing) compression-molded at 180 ° C is JIS
-Measured according to K7100.

Examples 1 to 8, Comparative Examples 1 to 3 After sufficiently replacing the stainless steel reactor equipped with a jacket and a stirrer with nitrogen, 5720 g of cyclohexane, 1 g of tetrahydrofuran, and 240 g of styrene were charged, and warm water was passed through the jacket. The material was set at about 70 ° C.

Thereafter, an n-butyllithium cyclohexane solution (1.4 g in pure content) was added to initiate polymerization of styrene. Ten minutes after the styrene was almost completely polymerized, 560 g of butadiene (1,3-butadiene) was added to continue the polymerization, and 15 minutes after the butadiene was almost completely polymerized and reached the maximum temperature, the coupling was completed. Agents (see Tables 1 and 2; Example 3
(As an 80% toluene solution only) at an equivalent ratio shown in Table 2 based on lithium of the living polymer to cause a coupling reaction. 15 from coupling agent addition
After a minute, 0.4 g of water was added. Immediately after charging the styrene, the inside of the system was continuously stirred by a stirrer.

Thereafter, the solution of the linear block copolymer was withdrawn, and 2,
6.4 g of 6-di-t-butyl-4-methylphenol, 4 g of tris (nonylphenyl) phosphite are added, the solvent is removed by steam-stripping the solution obtained, followed by a hot roll (120 g). C) to obtain a linear block copolymer.

Table 3 shows the basic physical properties of the thus obtained linear block copolymer of the present invention.

Examples 1 to 4 except that the type of the coupling agent was changed
In the same manner as in the above, linear block copolymers of Comparative Examples 1 to 3 were obtained. Similarly, the basic physical properties are shown in Table 3.

From Table 3, Examples 1 to 8 are different from Comparative Examples 1 to 3 in color tone, transparency, thermal stability and mechanical strength (tensile strength).
It can be seen that a linear block copolymer excellent in balance with the above is provided.

Examples 9 and 10 and Comparative Example 4 After sufficiently replacing the stainless steel reactor equipped with a jacket and a stirrer with nitrogen, 5,720 g of cyclohexane, 1 g of tetrahydrofuran, and 600 g of styrene were charged, and the contents were passed through the jacket by passing warm water through the jacket. Was set to about 80 ° C.

Thereafter, an n-butyllithium cyclohexane solution (1.2 g in pure content) was added to initiate polymerization of styrene. 10 minutes after the styrene had almost completely polymerized, 200 g of butadiene (1,3-butadiene) was added to continue the polymerization, and 15 minutes after the butadiene polymerized almost completely and reached the maximum temperature, the coupling was completed. An agent (see Tables 1 and 4) was added in an equivalent ratio of 1.0 based on lithium of the living polymer, and a coupling reaction was performed. 15 minutes after the addition of the coupling agent, 0.3 g of water was added. Immediately after charging the styrene, the inside of the system was continuously stirred by a stirrer.

Thereafter, the solution of the linear block copolymer was withdrawn, and 2,
6.4 g of 6-di-t-butyl-4-methylphenol and 4 g of tris (nonylphenyl) phosphite were added, the solvent was removed by steam-stripping the resulting solution, followed by hot roll (150 g). C) to obtain a linear block copolymer.

Table 4 shows the basic physical properties of the thus obtained linear block copolymer of the present invention and comparative products.

From Table 4, Examples 9 and 10 are compared with Comparative Example 4,
It can be seen that a linear block copolymer having an excellent balance between color tone, transparency, thermal stability and mechanical strength (Izod impact value) is provided.

(Effect of the Invention) The linear block copolymer produced by the production method of the present invention has an excellent balance among color tone, transparency, thermal stability, and mechanical strength.

Therefore, when the linear block copolymer is a thermoplastic elastic material, it can be used as a base polymer of a hot-melt type pressure-sensitive adhesive (which can also be used as a base polymer of a solvent-type pressure-sensitive adhesive), a road pavement, and the like. It is useful as an asphalt modifier such as a waterproof sheet.

Furthermore, impact resistance of footwear, toys, various resins, for example, styrene-based resins (including impact-resistant styrene-based resins and flame-retardant styrene-based resins), polyphenylene ether-based resins, olefin-based resins, polyamide-based resins, etc. It is also useful as a modifier.

On the other hand, when the linear block copolymer is a thermoplastic resin, it can be widely used for various uses such as being used as a transparent impact-resistant resin, and its industrial significance is large.

Claims (1)

(57) [Claims] 1. A method for producing a block copolymer using a monoalkenyl aromatic compound and a conjugated cyanene monomer in an inert hydrocarbon solvent using an organolithium compound as an initiator, comprising the steps of: A block copolymer consisting of a polymer block mainly composed of a monoalkenyl aromatic compound and a polymer block mainly composed of a conjugated diene is polymerized, and the peak molecular weight of the block copolymer in gel permeation chromatography (GPC) is determined. A step of preparing a living polymer, which is 1 × 10 ⁴ to 50 × 10 ⁴ in terms of standard polystyrene, and wherein the total amount of all the monoalkenyl aromatic compounds in the block copolymer is 10 to 90% by weight; And (ii) adding a diepoxy compound containing at least one compound selected from the following group to a living polymer based on lithium. As, 0.1 to 1.9 was added in the range of equivalent ratio, and wherein the more becomes that the step of performing the coupling reaction, method of manufacturing a linear block copolymer. (I) a general formula of the group; Wherein R is Wherein R ¹ and R ² are hydrogen or a C _{1 to} C ₂₀ alkyl group or alkoxy group or a phenyl group or a substituted phenyl group, and R ³ and R ⁴ are a C _{1 to} C ₂₀ alkyl group or an alkoxy group. R ⁵ is a linear or branched C ₁ -C ³⁰ (oxygen atom-containing) hydrocarbon group, l and m are integers from 0 to 4 and n is an integer from 0 to 10 It is. And a hydrogenated diepoxy compound thereof. (Group II) An alkylene oxide-containing diepoxy compound. However, the following compounds are excluded. Wherein R is R ³ is an alkylene group having 2 to 20 carbon atoms, n
Is an integer of 0 to 10, and the content of the compound having n of ₀ (hereinafter, referred to as n0 isomer) is 95% by weight or more]. (Group III) alicyclic diepoxy compound. However, the following compounds are excluded. Wherein R is Wherein R ¹ and R ² are hydrogen or an alkyl group having 1 to 20 carbon atoms or a phenyl group, n is an integer of 0 to 10,
Compound numbers are 0 (hereinafter referred to as n ₀ body) diepoxy compound content is indicated by the a] 95 wt% or more. (Group IV) Carboxylic compound-containing diepoxy compounds. However, the following compounds are excluded. Wherein R is Wherein R ¹ and R ² are hydrogen or an alkyl group having 1 to 20 carbon atoms or a phenyl group, n is an integer of 0 to 10,
Compound numbers are 0 (hereinafter referred to as n ₀ body) diepoxy compound content is indicated by the a] 95 wt% or more.